Wellbores are drilled to locate and produce hydrocarbons. A downhole drilling tool with a bit at one end thereof is advanced into the ground via a drill string to form a wellbore. The drill string and the downhole tool are typically made of a series of drill pipes threadably connected together to form a long tube with the bit at the lower end thereof. As the drilling tool is advanced, a drilling mud is pumped from a surface mud pit, through the drill string and the drilling tool and out the drill bit to cool the drilling tool and carry away cuttings. The fluid exits the drill bit and flows back up to the surface for recirculation through the tool. The drilling mud is also used to form a mudcake to line the wellbore.
During the drilling operation, it is desirable to provide communication between the surface and the downhole tool. Wellbore telemetry devices are typically used to allow, for example, power, command and/or communication signals to pass between a surface unit and the downhole tool. These signals are used to control and/or power the operation of the downhole tool and send downhole information to the surface.
Various wellbore telemetry systems may be used to establish the desired communication capabilities. Examples of such systems may include a wired drill pipe wellbore telemetry system as described in U.S. Pat. No. 6,641,434, an electromagnetic wellbore telemetry system as described in U.S. Pat. No. 5,624,051, an acoustic wellbore telemetry system as described in PCT Patent Application No. WO2004085796, the entire contents of which are hereby incorporated by reference. Other data conveyance or communication devices, such as transceivers coupled to sensors, may also be used to transmit power and/or data.
With wired drill pipe (“WDP”) telemetry systems, the drill pipes that form the drill string are provided with electronics capable of passing a signal between a surface unit and the downhole tool. As shown, for example, in U.S. Pat. No. 6,641,434, such wired drill pipe telemetry systems can be provided with wires and inductive couplings that form a communication chain that extends through the drill string. The wired drill pipe is then operatively connected to the downhole tool and a surface unit for communication therewith. The wired drill pipe system is adapted to pass data received from components in the downhole tool to the surface unit and commands generated by the surface unit to the downhole tool. Further documents relating to wired drill pipes and/or inductive couplers in a drill string are as follows: U.S. Pat. No. 4,126,848, U.S. Pat. No. 3,957,118 and U.S. Pat. No. 3,807,502, the publication “Four Different Systems Used for MWD,” W. J. McDonald, The Oil and Gas Journal, pages 115-124, Apr. 3, 1978, U.S. Pat. No. 4,605,268, Russian Federation Published Patent Application 2140527, filed Dec. 18, 1997, Russian Federation Published Patent Application 2,040,691, filed Feb. 14, 1992, WO Publication 90/14497A2, U.S. Pat. No. 5,052,941, U.S. Pat. No. 4,806,928, U.S. Pat. No. 4,901,069, U.S. Pat. No. 5,531,592, U.S. Pat. No. 5,278,550, and U.S. Pat. No. 5,971,072.
With the advent and expected growth of wired drill pipe technology, various types of circumstances will arise where it is necessary to connect a section of wired drill pipe to various types of uphole equipment or various types of tools or other downhole equipment. In some cases, the wired drill pipe may be incompatible with one or more components in the downhole tool and/or surface units.
It is, therefore, desirable to provide an interface to establish a communication link between a section of the wired drill pipe and the downhole tool and/or surface unit to facilitate communication between the downhole tool and a surface unit. It is further desirable to provide wellbore telemetry systems capable of providing added reliability, increased data rate, compatibility between a variety of downhole systems and increased power capabilities. Such a system is preferably capable of one or more of the following, among others: improving reliability, reducing communication failures, improving connectability, increase bandwidth, increase data rates, providing flexibility for a variety of downhole configurations and adapting wellbore telemetry tools to various wellsite configurations.